SYNTAX: two elements in a structure are coindexed if they have the same
referential index. Coindexing may
come about in different ways. Firstly, when an element undergoes
movement, all elements in the resulting
chain (the moved element itself, and any traces
it has left) bear the same index by convention. Alternatively, two NPs may be
assigned the same referential index, indicating either that they share the same
reference (in case the NPs in question may be interpreted as referential expressions)
or that one (typically a pronominal, an
anaphor, or an
anaphoric epithet) is interpreted as a
bound variable (in case the NP it is
coindexed with is interpreted as an operator).
The former case of coindexing plays a crucial role in the definitions of
chain and
antecedent government. The latter
case is relevant to binding theory.